Peak particle velocity for rockbursts in underground coal mines and for shot-hole explosions in open-pit mines

Abstract

The paper presents some results of in-situ seismological observations in hard-coal mines in the Ostrava-Karvina Coal Basin (OKCB) (Czech Republic) and in open-pit brown-coal and shale mines in Northwest and Central Bohemia, respectively. Trial measurements were aimed at investigating the peak particle velocity (PPV), which usually enables some criteria for the limitations of damage extent to be derived, e.g. of surface residential buildings, workings underground, failure and/or wall sliding. While rockbursts in hard-coal mines represent the source of recorded seismic waves, as opposed to that, shot-hole explosions for generating seismic waves in open-pit mines were used. Based on the regression analysis of the results of PPV experimental measurements vs. the square-root scaling factor for rockbursts and cube square factor for hole-shot explosion were applied, the slopes b of straight lines on the bilogarithmic scale were derived, i.e. b = −0.962 and b = −1.894, −1.843 and −2.256, respectively. On the other hand, PPV observed in the region of OKCB displayed values about 1–2 mm/s, while PPV at the sites in open-pit mines reached values roughly of 1–2 m/s due to a significantly smaller hypocentral distance, i.e. seismic source-velocity sensor distance.